<?php

/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2019/8/21
 * Time: 10:40
 */
class 运行时动态创建函数
{

}
if (count($_POST) > 0) {
    $prepped = create_function('$a', 'return trim($_POST[$a]);');
}
elseif (count($_GET) > 0) {
    $prepped = create_function('$a', 'return strtoupper($_GET[$a]);');
}
else {
    $prepped = create_function('$a', 'return false;');
}echo $prepped('file');